Mini version 20W30W40W50WX2 Blue tooth 5.0 digital power amplifier board knob to adjust the volume with switch 502L

Note: If you need a shell version, please take one for each of the two color categories. The 4 yuan material package does not contain power amplifiers, but only shell accessories!

Mini version 50Wx2 Blue tooth digital power amplifier board (knob to adjust the volume with switch)

Attention! The shell is a material package, which needs to be purchased separately and assembled by itself. The material package is given a screwdriver.

The potentiometer adjusts the volume, with a switch to control the volume, which is very suitable for DIY speakers.

If it is a metal box, you need to pull the Blue tooth antenna out.

The copper DC connector is adopted, which can withstand large current and does not generate heat.

Capacitor 470uf35V solid-state capacitor ensures the ability of storage and heat dissipation. Stable and continuous power supply is the premise of good sound.

The DC head wire can be compatible with the input power interface of this product, even if you do not have a DC head adapter or battery, it can be easily wired.

5.0 the Blue tooth version, the transmission efficiency is higher and the transmission distance is longer.

Precautions for use: The power switch on the board is a standby switch. After the switch is turned off, the machine is in a low-power standby state. It is necessary to completely turn off the power / unplug the DC plug on the machine for a long time.

Question Answer:

1. How to choose the power supply?

The power supply of the board is very important. The higher the voltage, the greater the current and the more sufficient the output power. If you only have 12V 1A, you can bring 3-4 inch speakers. If you are 19V 5A / above, there is no problem with 8-10 inches, and the power supply must be highly valued. If the voltage is too low, it is easy to cause sound distortion after sound amplification. If the current is too small, the horn will pull down the voltage, which will cause abnormal use / poor sound performance.

recommend use 18V19V24V power supply, current 3A / more. If you only have a 9V12V / 1A 2A power supply, you can also use it, but the power is low. Note that when using the volume, it may be distorted and affect the sound.

2. How to choose the speaker?

Commonly used speakers are generally 8 ohm, can not distinguish between positive and negative polarity, the effect is the same, 4 ohm speakers can also be used. If your horn power is small, it may be between 10W and 30W. The power supply voltage is smaller to prevent the horn from burning after amplifying the sound. For example, choose a power supply below 15V. If you are a 50W-200W speaker, you don't have to worry about the problem of burning out of the speaker. You can choose a 12-24V power supply. The higher the  voltage, the greater the output sound / power.

3. How to connect blue tooth?

Power on the power amplifier board, connect the horn, turn the audio knob indicator light on, turn on the mobile phone settings-blue tooth-search for "BT-WUZHI", and then click connect. after the connection is successful, there will be a ding dong tone. at this time, it is blue tooth mode, just play music, and the next power-on will automatically connect with the mobile phone.

4. It's okay to have a small voice. After the voice becomes louder, the voice becomes turbid?

The sound is distorted, please change the adapter power supply with a higher voltage level.

5. It's okay to have a small voice. After the voice becomes louder, there will be a sound jam?

The input power supply is insufficient, and the power supply itself is intermittently powered off. Please replace the power supply with a higher power supply. If the power is too large, the power amplifier board heats up seriously, and thermal protection occurs. Reduce power use / strengthen heat dissipation.